please help me with the last two questions

Starling Co. is considering disposing of a machine with a book value of $23,800 and estimated remaining life of five years. The old machine can be sold for $5,600. A new high-speed machine can be purchased at a cost of 74,300. It will have a useful life of five years and no residual value. It is estimated that the annual variable manufacturing costs will be reduced from $22,900 to $19,100 if the new machine is purchased, The five-year differential effect on profit from replacing the machine is (1) increased 64.610 b. Increase of 549.700 deco 519,700 d. decrease of 564 610 Which of the following methods of applying the cost-plus approach to product pricing includes only total manufacturing costs in the cost amount to which the markup is added? a total cost method b. product cost method c. variable cost method d. all of the choices